Plastic bottle for vending machines

ABSTRACT

A plastic bottle specially sized and configured for use in conventional vending machines. The bottle has structurally reinforced upper and lower portions providing additional strength and resistance to transversely imposed stacking and crushing forces. By internally thickening the plastic in the neck and upper shoulder portion, and in the base and lower sidewall portion, reinforcement is provided. The outer surface of the sidewall of the bottle is perfectly right-circular cylindrical in configuration, having no discontinuities such as ribs or label panels to impede smooth rolling through the can channels in a vending machine. The bottle shoulder includes one portion which is horizontal and substantially planar, and a another portion which is curved. The curved portion is particularly abrupt, providing increased contained volume and more closely resembling the corresponding portion of a can. A low profile,“finish” cap provides additional bottle volume, and provides a substantially large surface to engage the wall of the vending machine channel. A dot of adhesive is ejection applied between a lower edge of the cap and the neck of the bottle, to provide tamper proof indicator.

CROSS-REFERENCE TO RELATED APPLICATION

Applicant has a co-pending design patent application, Ser. No. 29/116,819, filed Jan. 12, 2000, relating to the same general subject matter of the present application.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates generally to cap-sealed containers for consumables, such as beverages or candy, or other relatively small items. More specifically, the invention pertains to a plastic bottle having a special size, configuration, wall thickness, and rolling characteristics which allow it to be used in can vending machines, without damage or jamming.

2. Description of the Prior Art

The earliest beverage vending machines were designed for use with glass bottled beverages. As many of the bottled beverages had different, and even branded physical characteristics, dedicated beverage machines were common. That is to say, only a particular brand of beverage was available in a vending machine, and only that brand would work in that dedicated machine. Thus, these early vending machines were designed to accommodate, store, and vend only a bottle of a certain size and configuration.

Later, when tin cans and aluminum cans became available, the beverage industry eventually standardized the size and configuration of the cans, so a single vending machine would have the capability of vending many different brands of beverages. Because the size and configuration of the cans were standardized, the container storage and delivery systems of the vending machines were able to handle cans from different manufacturers without jamming, or causing damage to the containers.

The beverage industry has more recently embraced plastic bottles as an alternative container for the same beverages which were previously, and in some cases still are, contained in metal cans. PET containers, for example, have become particularly popular for containing the relatively large 2 and 3 liter quantities of soft drinks. These containers are recyclable, easy to label, and convenient for the consuming public to handle and use. Other plastic bottles, such as 10 or 12 oz. containers, have also come into widespread use, especially in six-packs. Although some of these smaller containers are sold individually, they are marketed in store refrigerators, or on store shelves.

However, a successful adaptation of plastic bottles for use in vending machines, has not been made. A variety of different container feeding systems are used in vending machines. One type of feeding system uses a serpentine, or S-shape container channel, extending from a container loading end to a container delivery end. In another system, termed a “front load”, containers are stacked in vertical rows within containment channels, in the front portion of the vending machine. Lastly, there are “drop load” machines, in which the containers are loaded into a channel which extends first rearwardly and then downwardly through the vending machine, before it exits at the front of the machine. While metal cans perform very reliably in these feeding systems, plastic bottles of conventional design do not.

There are two principal problems with prior art plastic bottles deigned for use in vending machines: (1) they roll unevenly, and therefore, have a tendency to jam in the container feeding or transport channels of the vending machine; and, (2) when stacked for storage within a vending machine, the plastic bottles crush or crack, under the cumulative weight of overlying bottles.

Some prior art designs use one or more circumferential ribs in the median sidewall portion of the bottle, for strength. Unfortunately, these ribs can cause the previously mentioned uneven and erratic rolling characteristics, owing to the surface discontinuities. Other prior art designs use rounded shoulders, in the upper portion of the bottle. This configuration does not match well with the can feeding channels within vending machines, and causes frequent jamming, as well.

Finally, the use of a conventional locking ring as a tampering indicator requires that the neck of prior art plastic bottles be a certain minimum length, so there is sufficient room on the lower end of the neck for the locking ring. However, since the overall length of the bottle and its neck cannot exceed the existing channel width, approximately an ounce of potential volume for the contained beverage is lost. Thus, most prior art plastic bottles using the locking ring indicator have a maximum volume in the range of 10-10.5 ounces.

Therefore, the need exists for a plastic bottle configuration and construction, which is strong enough to withstand container stacking within a vending machine.

The need also exists for a plastic bottle which does not jam within the container storage and transport channels of a vending machine.

The need also exists for a plastic bottle which may contain quantities of articles or food items needing a chilled environment, and which will store and transport successfully in a vending machine.

And finally, the need exists for a plastic bottle which includes a tamper-proof indicator system which consumes no additional bottle length, and provides improved container volume.

SUMMARY OF THE INVENTION

The plastic bottle of the present invention includes structurally reinforced upper and lower ends, providing additional strength to resist to laterally imposed stacking and crushing forces. Strategic reinforcement is provided by internally thickening the plastic in the neck and the shoulder portion, and in the base and the lower sidewall portion. Proportionally, the plastic in the reinforced ends is approximately four times as thick the standard bottle wall thickness, found in an intermediate sidewall portion of the bottle.

Because the reinforcement makes the plastic bottle sufficiently strong to withstand the forces generated by vertical stacking of containers in a vending machine, no circumferential sidewall ribs are necessary. Having a smooth sidewall surface with no convolutions or discontinuities, the plastic bottle of the present invention is less likely to rotate sideways, or jam, within the container feeding system of a vending machine.

A low profile cap is threadably installed over an externally threaded neck on the upper end of the cap. The weight of additional thickness of plastic in the upper end of the bottle, combined with the weight of the cap, aid in balancing the bottle so it will roll about its axis more smoothly. This characteristic of the bottle makes it less susceptible to jamming in a vending machine.

The shoulder portion of the bottle includes a sharply curved outer edge, which bends outwardly and downwardly to transition to the bottle's intermediate sidewall portion. The configuration of this curved outer edge more closely approximates the shape of a metal can, so that the plastic bottle will roll more freely and predictably in the container feeding system in a vending machine.

The neck portion of the bottle is shorter than prior art designs, which use a longer neck to accommodate a lock ring to evidence tampering with the bottle. Use of a shorter neck provides more fluid containment in the body of the bottle. Instead of a tamper ring, the present invention uses a small dot of frangible adhesive extending between a lower edge of the cap and an exterior surface of the neck. When the user unscrews the cap, the adhesive breaks off, evidencing that the bottle cap has been unscrewed. These and other objects and features of the present invention will become apparent in the detailed description and the accompanying drawings to follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded, perspective view of the plastic bottle and cap of the present invention;

FIG. 2 is a cross-sectional view, taken on the line. 2-2, in FIG. 1;

FIG. 3 is a top plan view of the plastic bottle, with the cap removed;

FIG. 4 is a bottom plan view of the plastic bottle;

FIG. 5 is a fragmentary, perspective view of the upper end of the plastic bottle including a 28 mm cap, a portion of the cap being broken away to show the neck portion of the bottle;

FIG. 6 is a view as in FIG. 5, but showing a 45 mm cap;

FIG. 7 is a fragmentary, front elevational view of a “front load” vending machine, showing the plastic bottles in vertically stacked relation; and,

FIG. 8 is a fragmentary, cross-sectional view, taken to an expanded scale, showing the upper and lower ends of the bottle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning now to FIG. 1, the bottle 11 of the present invention has an upper end 12, an intermediate sidewall portion 13, and a lower end 14. Bottle 11 has an overall height of 121 mm (approximately 4¾″) and an overall width of 68 mm (approximately 2 11/16″). These overall dimensions are selected generally to correspond to the exterior dimensions of the aluminum cans dispensed by the standard American can vending machine. However, there is nothing critical as such with these dimensions, and they could be changed as required, in the event that a plastic bottle was required for a vending machine having different dimensions for its container storage and feeding channels.

As shown in greater detail in FIG. 8, upper end 12 includes a right-circular cylindrical neck portion 16 and a shoulder portion 17. Neck portion 16 has external threads 18, and includes an open upper end 19. Shoulder portion 17 has a substantially planar, annular section 21, and a curved transition section 22. A lower end of the neck portion 16 extends in perpendicular fashion from an inner periphery of the annular section 21. The curved transition section 22 extends outwardly and downwardly from an outer periphery of the annular section 21.

A low-profile cap 20 a, including its own internal threads, is threadably attached to the bottle 11 over external threads 18. Cap 20 a is not a conventional beverage container cap. Cap 20 a is termed a 38-400 finish cap, in the industry, and is manufactured by Alcoa and/or Topseal. Although cap 20 a is 38 mm in diameter, other diameters may be used in conjunction of course with different diameters for neck portion 16. Other popular sizes which may be used with the bottle 11 would be the 28mm cap 20 b and the 45 mm cap 20 c, shown respectively in FIGS. 5 and 6.

It should be noted that in using these caps in conjunction with bottle 11, no separate tamper-evidencing locking ring is used. Although not currently required by law for beverages, such locking rings are now in widespread use. Such locking rings are effective to warn the consumer, if the beverage bottle they are about to purchase or consume has previously been opened by another. The problem they pose is the addition of height to the bottle. Bottle necks must be made longer, or conversely cannot be made shorter, if a locking ring is present. Since a design objective of the present invention is to produce a plastic bottle which will contain close to 12 ounces of beverage, while at the same time work as the functional equivalent of cans in currently available vending machines, bottle height is both limited and critical.

The bottle 11 of the present invention has a contained volume of approximately 11.5 ounces, while meeting the height and width standard of a beverage can. This is primarily accomplished by not using a locking ring and by configuring the curved transition section 22 so that it closely resembles the corner of a can.

As to the elimination of the locking ring, this space-saving measure allows the caps 20 a-20 c to fit snugly down on neck portion 16. In lieu of the locking ring, an adhesive dot 25, shown in FIG. 5 and 6, is employed for tamper-evidence. Adhesive dot 25 is applied between a lower edge of cap 20 a-20 c, and an adjacent surface of neck portion 16. It may also be desirable to apply two or more dots, in spaced relation around the cap to provide even more indicators. Preferably, dot 25 is a hot-melt adhesive or wax, ejection-applied between the cap and the neck following the bottling operation. Hot-melt adhesive and wax are effective materials to evidence tampering, as they initially provide rotational resistance to cap opening. Then, if sufficient force is applied, the material breaks free either from the cap or from the external surface of the neck portion, or it simply falls away. Thus, a consumer would know, both from visual inspection and from reduced rotational resistance to opening, if tampering had occurred. Hot-melt is also very cost effective and easy to implement, as tamper-evidence, when compared to the locking ring method, or the shrink wrap method.

Regarding the configuration of the curved transition section 22, it should be noted that it has an unusually small radius of curvature. As a consequence, it closely resembles the upper corner of a beverage can. This feature provides additional container volume, over the prior art which displays gradually rounded shoulders in this region. This feature also provides a container configuration which functions more like a can in a vending machine, owing to its shape and the weight distribution of the contained liquid.

As another important feature of the present invention, strategic reinforcement of the plastic bottle is provided both at the upper end 12 and at the lower end 14. The upper end 12 has a first wall thickness 23, generally extending throughout neck portion 16 and shoulder portion 17. Thickness 23 is approximately 3.2 mm (⅛″) in the preferred embodiment, but this dimension may be increased or decreased depending upon the size of the plastic bottle and its application. The additional plastic material which results in this thickness, is formed during the molding of the bottle, and extends inwardly, into the bottle volume. In other words, the enhanced thickness of the plastic material is not reflected in the outer surface of the bottle. Thus, neither the appearance nor the rolling surface of the bottle 11 is adversely affected by the addition of this plastic reinforcement material.

Toward a lower end of curved transition section 22, the wall thickness quickly tapers down, first to 1.6 mm ( 1/16″), and then to 0.8 mm ( 1/32″), where an upper end of intermediate sidewall portion 13 begins. The 0.8 mm wall thickness at this upper end characterizes a second wall thickness 24. From the top to the bottom of right-circular cylindrical sidewall portion 13, the thickness 24 remains substantially uniform. It is also important to note that the outside configuration of sidewall portion 13 includes no rib indentations, label panels, or other surface anomalies which may interfere with smooth rolling of the bottle.

In the preferred embodiment of the bottle 11 disclosed herein, the numerical ratio between the first and second wall thicknesses is approximately 4 to 1. However, there is no particular criticality to this ratio. It is sufficient for most applications that the first wall thickness is substantially greater than the second wall thickness, so that the former will provide a reinforcement function. If the ratio is too low, the overall strength of the bottle will not be sufficient. If the ratio is too high, molding difficulties may arise, bottle cost will rise, and the loss of contained volume will become a factor.

For a plastic bottle of the size of bottle 11, the second sidewall thickness of 0.8 mm is generally in conformance with the existing industry standard. Providing the bottles are stored and transported in such a way that forces which are laterally, or transversely imposed upon the bottles are minimal, the sidewalls for the entire bottle may be 0.8 mm thick. However, if these forces are more than minimal, such as those encountered in the storage and delivery mechanisms of vending machines, the bottle sidewalls may crack or crush.

Thus, to address this problem, the lower end 14 of the bottle is provided with strategic reinforcement as well. Lower end 14 includes a lower, curved sidewall portion 26 and a base 27. Curved sidewall portion 26 begins at a bottom edge of intermediate sidewall portion 13, and continues until it reaches the outer edge of base 27. As it curves downwardly and inwardly, sidewall portion 26 quickly increases in thickness from the second wall thickness 24, to a substantially greater first wall thickness 23. The first wall thickness 23 continues for the full extent of base 27. Base 27 is circular, and includes a convex central region, protruding inwardly within the bottle, and an outer edge connected to a lower edge of said curved sidewall portion 26.

Thus, both the upper and lower ends of the bottle 11 are provided with reinforced regions which are particularly resistive to transversely applied, compressive forces. Owing to the substantially increased thickness of the plastic in these strategic regions of the bottle, the ability of the bottle 11 to withstand forces which are encountered in vertical stacking of bottles is significantly enhanced. Making particular reference now to FIG. 7, a portion of a container delivery channel 31 in a typical front-loading vending machine is shown. The channel 31 includes a plurality of bars 32, defining the transverse dimensions of the channel. A rotatable gate 33 is provided at the bottom of the channel, for allowing individual ones of containers to be released into a container delivery chute (not shown) of the machine.

A plurality of containers 11 is arranged within the channel in stacked, vertical relation. With the axes of the bottles horizontal, the compressive forces of the bottles are transmitted transversely, through the sidewall and ends of the bottle, to the bottle below. Thus, the cumulative weight of four bottles, represented by F1, is impressed upon the bottom bottle. And, the cumulative weight of five bottles, represented by F2, is supported by gate 33.

As the plastic material within the intermediate sidewall portion 13 of the containers is relatively thin, the bottom bottles might distend or break under the cumulative weight of the upper bottles, unless additional reinforcement is provided. Because the bottles 11 of the present invention have first and second reinforcement means, provided by the thickened plastic precisely in the regions where F1 and F2 show the application of compressive forces, bottles 11 are able to withstand the rigors of the vending machine bottle storage and delivery system.

It will be appreciated, then, that I have disclosed an improved plastic bottle including structural reinforcement in critical regions of the bottle which resist crushing or damage to the bottle, owing to the application of compressive, transversely applied forces. I have also disclosed a unique tamper-indicator, which is inexpensive, easy to apply, and allows full utilization of available container space to enhance the containment volume of a plastic bottle. 

1. A plastic bottle, comprising: a. an upper end, including a neck portion and a shoulder portion, said neck portion having external threads and an open upper end, said shoulder portion having a substantially planar annular section and a curved transition section, a lower end of said neck portion extending perpendicularly from an inner periphery of said planar section, said curved transition section extending outwardly and downwardly from an outer periphery of said planar section, said upper end having a first wall thickness; b. a lower end, including a lower, curved sidewall portion and a base, said base being circular and having a convex central region, extending inwardly within the bottle, and an outer edge connected a lower edge of said curved sidewall portion, said lower end having said first wall thickness; c. an intermediate sidewall portion between said upper end and said lower end, said intermediate sidewall portion having a second wall thickness, said first wall thickness being substantially greater than said second wall thickness.
 2. A bottle as in claim 1 in which said first thickness is ⅛″ and said second thickness is 1/32″.
 3. A bottle as in claim 1 in which the plastic is 25 or higher grain.
 4. A bottle as in claim 1 further including a cap having internal threads, said cap being sized for screwing over said external threads of said neck portion.
 5. A bottle as in claim 4 in which said cap has a lower edge, and in which a dot of adhesive material is applied to said lower edge and an adjacent external surface of said neck portion, said adhesive material being sufficiently hard so initially to provide rotational resistance and then to break free either from said cap or said external surface, when said cap is unscrewed from said bottle.
 6. A bottle as in claim 5 in which said adhesive material is a hot melt adhesive or wax.
 7. A bottle as in claim 1 in which said first wall thickness is approximately four times as thick as said second wall thickness.
 8. A bottle as in claim 1 in which said intermediate sidewall portion has an outer diameter of approximately 2 11/16″, and said bottle has a height, extending from a lowermost edge of said lower end to said open upper end of said neck portion of approximately 4¾″.
 9. A bottle as in claim 1 in which said neck portion is right-circular cylindrical, and has a diameter of approximately 28 mm, 38 mm, or 45 mm.
 10. A plastic bottle, comprising: a. an upper end formed from plastic, including a neck portion and a shoulder portion, said neck portion having external threads and an open upper end, said shoulder portion having a substantially planar annular section and a curved transition section, a lower end of said neck portion extending perpendicularly from an inner periphery of said planar section, said curved transition section extending outwardly and downwardly from an outer periphery of said planar section, said upper end including first reinforcement means for resisting transversely compressive forces; b. a lower end formed from plastic, including a lower, curved sidewall portion and a base, said base being circular and having a convex central region, extending inwardly within the bottle, and an outer edge connected a lower edge of said curved sidewall portion, said lower end including second reinforcement means for resisting transversely compressive forces; and, c. an intermediate sidewall portion formed from plastic, said sidewall being between said upper end and said lower end, said intermediate sidewall portion having a substantially uniform sidewall thickness.
 11. A bottle as in claim 10 in which said upper end has an inner surface and said lower end has an inner surface, and in which said first reinforcement means includes additional plastic material on said inner surface of said upper end effective to make said upper end thicker than said sidewall thickness, and said second reinforcement means includes additional plastic material on said inner surface of said lower end effective to make said lower end thicker than said sidewall thickness.
 12. A bottle as in claim 11 in which said upper end and said lower end are approximately ⅛″ in thickness, and said sidewall thickness is approximately 1/32″.
 13. A bottle as in claim 10 in which the plastic is 25 or higher grain.
 14. A bottle as in claim 10 further including a cap having internal threads, said cap being sized for screwing over said external threads of said neck portion.
 15. A bottle as in claim 14 in which said cap has a lower edge, an in which a dot of adhesive material is applied to said lower edge and an adjacent external surface of said neck portion, said adhesive material being sufficiently hard so initially to provide rotational resistance and then to break free either from said cap or said external surface, when said cap is unscrewed from said bottle.
 16. A bottle as in claim 15 in which said adhesive material is a hot melt adhesive or wax.
 17. A bottle as in claim 10 in which said intermediate sidewall portion has an outer diameter of approximately 2 11/16″, and said bottle has a height, extending from a lowermost edge of said lower end to said open upper end of said neck portion of approximately 4¾″.
 18. A bottle as in claim 10 in which said neck portion is right-circular cylindrical, and has a diameter of approximately 28 mm, 38 mm, or 45 mm. 